Hi Monks,

Is there ever a difference in semantics between

sub foo {
    ....
    my $value = <expression>;
    return $value;
}

and

sub foo {
    ....
    return <expression>;
}

?

I ask this because I am experiencing a negative interaction between the Komodo remote debugger and the CPAN module DBIx::transaction. When debugging code that commits a transaction, I get an error like this:

panic: attempt to copy freed scalar 350d010 to 15c7b68 at
/usr/share/komodo/perllib/perl5db.pl line 4341, <STDIN> line 1.

Strangely, I have found that I can fix the error by changing the definition of close_transaction in DBIx/Transaction/db.pm from

sub close_transaction {
    my $self = shift;
    my $method = shift;
    my $code = DBI::db->can($method);
    $self->{private_DBIx_Transaction_Level} = 0;
    $self->clear_transaction_error;
    $self->transaction_trace($method);
    my $rv = $code->($self, @_);
    return $rv;
}

to

sub close_transaction {
    my $self = shift;
    my $method = shift;
    my $code = DBI::db->can($method);
    $self->{private_DBIx_Transaction_Level} = 0;
    $self->clear_transaction_error;
    $self->transaction_trace($method);
    return $code->($self, @_);
}

to me, it looks like my change should have no effect, and yet it eliminates the panic. What's going on here? Could it be a bug in the Komodo remote debugging libraries, or in the Perl implementation, or in DBIx::Transaction?

Thanks

In reply to Attempt to copy freed scalar and return value semantics by turkanis

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